I'm making designs for my own armor (I'm not going to have it built until I stop growing), but keep running in to one big problem: heat. My original idea was to put small tubes of water in the body suit that all connect to a pump on my thigh concealed by a holster and kama. The idea is that the movement of the water getting pumped through the tubes keeps me from overheating. The problems with this is that it would be very hard, very expensive, and I don't know where to get a small water pump, or if they even exist. Any ideas, vode?

Aliit ori'shya tal'dinAliit ori'shya tal'dinFamily is more than bloodline

There'd also be a problem with the heat from that motion. I'd look into different materials for the bodysuit, and see what firemen, SWAT, etc uses in their uniforms to keep them cool, because they wear a lot of heavy stuff. Also, if it comes down to it and you just have to endure it, work on keeping hydrated and keeping your electrolytes up so you can keep sweating (gross, but you do it for a reason, and that reason is to keep cool).

may my mind stroll about hungry and fearless and thirsty and supple~ e e cummings

Engineer here. I actually looked into designing active cooling for a set of beskar'gam, and while it's technically possible, it'd chew through batteries like candy. You'd be better off with a fan in your buy'ce and ice packs on your torso, like Vlet and Aarlaya suggested.

That said, there are ways to redistribute heat better. If you've got spots in your armor where the heat's building up unbearably, run a wide strip of copper (with cloth padding) from the heat area to one of the cold packs. Copper's a great thermal conductor, and as long as you've got ice left, it'll leech away some of the heat. Just be careful not to let any copper-paneled pieces of your armor get a lot of direct sun, or you'll get the opposite effect.

Of course, you have a lot of body heat, so if you've got a spot you want cooled far away from an ice pack, make sure the copper strip is well-insulated between Point A and Point B or else you'll use up all of the cold before it gets where it needs to go.